Holland's Annemiek van Vleuten is in intensive care with concussion and three fractures to her lower back following her crash in the Olympic road race on Sunday.
Van Vleuten was admitted following the horrendous downhill crash 10 kilometres from the end of the 137km race, which she was leading at the time.
A Dutch Olympic Committee official revealed she sustained "three small fractures in her spine, a heavy concussion and she has to stay on the intensive care overnight".
Van Vleuten's compatriot Anna van der Breggen went on to win the race at Copacabana beach.
Van der Breggen said: "I was really shocked when I saw the crash and it didn't look good but I had to focus and keep on with the race."
Immediately after the race, the UCI, cycling's world governing body, said in a statement: "Ms van Vleuten is conscious, able to communicate. Further medical checks currently being made at the hospital."
The crash allowed Mara Abbott of the United States to take the lead, with Sweden's Emma Johansson, Elisa Longo Borghini of Italy and Van der Breggen Holland in pursuit.
Abbott had an advantage of almost 40 seconds as the descent flattened out, but was caught in the final 200m and denied a medal.
Van der Breggen took gold, Johansson silver and Longo Borghini bronze.
It was agonising for Abbott as she missed out on a medal of any colour.
So too did British world champion Lizzie Armitstead who had been provisionally suspended by UK Anti-Doping on 11 July for three whereabouts 'failures', but was cleared to race last week.
Later on Sunday, the Dutch cycling federation tweeted "Van Vleuten conscious, transported to the hospital for further examination. KNWU doctor is with her."
Van Vleuten bij bewustzijn vervoerd naar het ziekenhuis voor verder onderzoek. KNWU dokter is bij haar.
— KNWU (@KNWU) August 7, 2016
The cyclist herself later took to social media to reassure fans of her condition.
I am now in the hospital with some injuries and fractures, but will be fine. Most of all super disappointed after best race of my career.
— Annemiek van Vleuten (@AvVleuten) August 8, 2016
The race was frenetic, relentless and full of attacking drama from the start, but only when the bunch came on to the coastal road, with winds buffeting them from the Atlantic did a significant split happen, with around 40km to go.
Marianne Vos, Australia's Gracie Elvin, Germany's Trixi Worrack and France's Pauline Ferrand Prevot were all involved in a seven-rider break.
The USA led the chase, but the escapees were over one minute ahead entering the concluding loop of the Vista Chinesa, where the race would be won.
The breakaway group fractured up the climb as the dwindling peloton caught up.
Three Americans and three Dutch riders were in the leading group.
Vos fell back, her domestique duty done, as the contenders were further whittled down.
Armitstead tried to time-trial up the climb, concentrating on her own tempo, as the gap to the leaders grew.
Van der Breggen and Van Vleuten were joined at the front of the race by Borghini and Evelyn Stevens of the USA as South Africa's Ashleigh Moolman-Pasio dropped back.
Van Vleuten made her move, with USA's Mara Abbott tracking her.
Johansson, Borghini and Van der Breggen were ahead of the Briton in the second group, with the Dutchwoman not contributing to the chase as her team-mate was up ahead.
Then came the descent to the finish, which, for a second straight day, proved decisive.
